Zeki Karasu

Ege University, Ismir, İzmir, Turkey

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Publications (105)568.47 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: The present study was designed to determine seroprevalence of Hepatitis B and C virus infections and risk factors in Turkish general population. The subjects were enrolled from urban and rural areas of the predetermined 23 EUROSTAT NUTS 2 region. A two -stage stratified sampling method was used to select participants from these regions. Participants' (n=5460; 50.9% females; mean(SD) age: 40.8(14.7) years) socio-demographics, clinical characteristics and risk factors were recorded at home visits. The seropositivity rates for HBsAg, anti-HCV, anti-HBs and anti-HBc total were found as 4.0%, 1.0%, 31.9%, and 30.6%, respectively. Among HBsAg-positive cases, 94.5% were anti-HBe-positive, 70.2% HBV-DNA-positive, and 2.8 % anti-HDV total positive; 99.1% of HBV subjects were of genotype D. Close contact with hepatitis patient (OR, 3.24; 95% CI, 2.25 to 4.66; p<0.001), living in South-eastern region (OR, 2.74; 95% CI, 1.7 to 4.45; p<0.001), male gender (OR, 1.77; 95% CI, 1.28 to 2.46; p<0.001), being married (OR, 1.62; 95% CI,1.02 to2.57; p=0.038, educational level less than high school (OR, 1.53; 95% CI, 1.04 to 2.26; p=0.03), orodental interventions (OR, 1.54; 95%CI, 1.01 to 2.35; p=0.047) and use of non-disposable syringe history (OR, 1.4; 95% CI, 1.01 to 1.96; p=0.045) were significant determinants of HBsAg positivity. Age≥50 years (OR, 2; 95% CI, 1.09 to 4.3; p=0.026) was the only significant predictor of anti-HCV positivity. In conclusion, our findings revealed an HBsAg positivity in 4% and anti-HCV positivity in 1% of adult population and at least 1/3 of the population has been exposed to HBV infection in Turkey. Copyright © 2015. Published by Elsevier Ltd.
    Clinical Microbiology and Infection 07/2015; DOI:10.1016/j.cmi.2015.06.028 · 5.77 Impact Factor
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    ABSTRACT: The recently reported benefit of telbivudine on renal function has not been systematically studied in long-term liver transplant (LT) recipients who are at high risk of renal impairment. We aimed to examine whether switching lamivudine therapy to telbivudine may improve renal functions in LT recipients who have impaired renal function. This single-center, prospective cohort study enrolled LT recipients who were on lamivudine for hepatitis B virus (HBV) prophylaxis and who had renal impairment for at least 1 year. Lamivudine was switched to telbivudine. The primary outcome was to evaluate the change in renal function at week 12, 24, 36 and 48. The secondary outcomes were to assess the efficacy of telbivudine for HBV prophylaxis and the safety profile of telbivudine in the post-transplant setting. After 45 patients were enrolled, the study was terminated early due to increased rates of polyneuropathy/myopathy. During median 64 weeks of telbivudine treatment, eGFR increased in 34 (76%) patients. The improvement in renal function was prominent after 24 weeks of telbivudine treatment. Telbivudine was effective in prophylaxis of HBV recurrence. Twenty-six patients (58%) developed polyneuropathy and/or myopathy. The 1-year estimated incidence of polyneuropathy/myopathy was 28%. Diabetes was the strongest predictor of polyneuropathy/myopathy (hazard ratio, 4.13; 95% CI, 1.49 - 11.50; p = 0.007). In conclusion, although it seems to have a favorable effect in the improvement of renal function and to be effective in the prevention of HBV recurrence, the high risk of polyneuropathy and myopathy hamper the use of telbivudine in LT recipients. This article is protected by copyright. All rights reserved. © 2015 American Association for the Study of Liver Diseases.
    Liver Transplantation 04/2015; 21(8). DOI:10.1002/lt.24131 · 4.24 Impact Factor
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    ABSTRACT: Introduction: The aims of this study were to detect the seroprevalence of hepatitis A, B, and C viruses in Turkish alcoholic cirrhotics, and to evaluate the impact of hepatitis B infection on clinical profile at first admittance. Methodology: Serological markers for hepatitis A, B, and C viruses in 300 alcoholic cirrhotics diagnosed between January 1994 and December 2012 were retrospectively reviewed. Among them, 148 eligible patients were divided into group 1 (HBsAg positive, n = 43) and group 2 (HBsAg and anti-HBc negative, n = 105). Clinical characteristics at first admittance of groups 1 and 2 were compared. Results: The seroprevalence of anti-HAV total, HBsAg, and anti-HCV was found to be 91.5%, 16.3%, and 8.2%, respectively. The prevalence of hepatocellular carcinoma was higher in the HbsAg-positive group compared to HbsAg- and anti-HBc-negative group (16.3% vs. 2.9%, p = 0.007). Other clinical features were similar in the two groups. Conclusions: Alcoholic cirrhotics have higher frequencies of HBsAg and anti-HCV than the general population. These patients should be investigated for coexistent HBV and HCV infections, and HBV vaccination should not be neglected. Alcoholic cirrhotic patients with concomitant HBV infection should be closely screened for hepatocellular carcinoma.
    The Journal of Infection in Developing Countries 03/2015; 9(03). DOI:10.3855/jidc.6002 · 1.14 Impact Factor
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    ABSTRACT: Background We aimed to measure the diurnal changes of critical flicker frequency in healthy subjects and cirrhotic patients and to investigate their relationship with sleep disturbance. Methods Cirrhotic patients and healthy volunteers were included. All groups completed the Pittsburgh Sleep Quality Index and a simple sleep questionnaire. Sleep disturbance was defined as a Pittsburgh Sleep Quality Index score of >5. Critical flicker frequency was measured twice a day to detect diurnal abnormalities. Results Overall, 59 cirrhotic patients (54.2% males, Mean Age 59 ± 11 years) and 18 controls (39.9% males, Mean Age 58 ± 9 years) were included. Sleep disturbances were more common in cirrhotics (66.1%) than controls (38.9%, p < 0.05). In cirrhotics, the critical flicker frequency was not related to decompensation. The nocturnal values were higher than the morning values in cirrhotics (64.4%), but not in controls (p < 0.0001). Additionally, sleep disturbances were more common in cirrhotics who had higher nocturnal values (p < 0.05). Conclusions Changes in the diurnal critical flicker frequency were observed in cirrhotics but not in controls. Sleep disturbances in cirrhotics appear to be associated with deviations of the diurnal rhythm of critical flicker frequency rather than with clinical parameters such as the clinical stages of cirrhosis and the Model For End-Stage Liver Disease and Child–Pugh scores.
    Digestive and Liver Disease 12/2014; 46(12). DOI:10.1016/j.dld.2014.08.031 · 2.96 Impact Factor
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    ABSTRACT: Sleep disorders (SDs) are common in cirrhotics and are often associated with hepatic encephalopathy. SDs negatively affect patients' daily activities and work efficiency. For this reason, early diognosis is important. The methods used for diagnosis of SDs are not practical and need longer periods of application and evaluation. In this study we aimed to investigate sleep disorders and related clinical parameters in liver cirrhosis and also want to investigate the using of Sleep Timing and Sleep Quality Screening questionnaire (STSQS), a simple form with a short application time, for diagnosis of SDs and its correlation with Pittsburg Sleep Quality Index (PSQI) form. Cirrhotic patients and age-matched healthy volunteers were enrolled. Patients were excluded from the study if they had neuropsychiatric disease or used excessive alcohol or drugs known to affect sleep. Both groups completed validated Turkish form of PSQI and STSQS. SD was defined as PSQI score (0-21) of >5 or STSQS≥5. 131 cirrhotic patients and 18 healthy volunteers were enrolled. SDs in cirrhotics and control group were detected 56.5% and 27.8% by PSQI, 49.6% and 16.7% by STSQS respectively, SDs is the most frequent in the Child C patients, and the least frequent in the Child A patients (p>0,05). No correlation was found between the MELD score and SDs. SDs were more common in cirrhotic patients with hypoalbuminemia and low hemoglobin levels. In addition, the patients with decompensated cirrhosis had more frequently SDs than the patients with compensated cirrhosis. In the patient group, sleep latency and total sleep time, sleep parameters were correlated with SDs. STSQS had statistical significant correlation with PSQI for diagnosis of SDs. SDs are common in cirrhotics and STSQS could be an appropriate and practical method for diagnosis of SDS in these patients. We can use it in cirrhotic patients at outpatient clinics. This article is protected by copyright. All rights reserved.
    Liver international: official journal of the International Association for the Study of the Liver 02/2014; 34(8). DOI:10.1111/liv.12485 · 4.85 Impact Factor
  • Ilker Turan · Suna Yapali · Omer Ozutemiz · Zeki Karasu
    Transplantation 02/2013; 95(3):e15-6. DOI:10.1097/TP.0b013e31827c650e · 3.83 Impact Factor
  • Journal of Hepatology 04/2012; 56:S193. DOI:10.1016/S0168-8278(12)60505-4 · 11.34 Impact Factor
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    ABSTRACT: Certain drugs including oxyphenisatin, methyldopa, nitrofurantoin, diclofenac, interferon, infliximab, pemoline, minocycline, atorvastatin, and rosuvastatin can induce hepatocellular injury that mimics autoimmune hepatitis. Whether drugs and herbs unmask or induce autoimmune hepatitis or simply cause a drug-induced hepatitis with accompanying autoimmune features is unclear. We describe the clinicopathologic details of eight cases with ornidazole-induced hepatitis with autoimmune features. Patients who presented with acute hepatitis between February 2001 and March 2009 were reevaluated for the etiology of liver disease. Patients with acute viral hepatitis, metabolic liver disease, vascular liver disease such as Budd-Chiari syndrome, biliary obstruction, or alcohol consumption were excluded. The autoimmune hepatitis scores, which were calculated at the time of diagnosis according to the criteria of the International Autoimmune Hepatitis Group, were recorded. In addition, the simplified criteria of the same group were applied retrospectively to each patient. Patients with ornidazole-induced toxic hepatitis with autoimmune hepatitis were included to constitute the study group of this report. All patients underwent initial liver biopsy, and one patient underwent liver biopsy three years later. All biopsies were scored according to the hepatitis scoring system by Ishak et al. (10). Overall, eight patients (all female) were diagnosed as drug-induced autoimmune hepatitis. With the exception of one patient, all were treated with prednisolone 30 mg/day + azathioprine 50 mg/day. The prednisolone dose was tapered according to the decrease in the level of transaminases. A two-year treatment program was planned for all patients. Ornidazole may cause drug-induced autoimmune hepatitis. Withdrawal of the drug may not provide the recovery despite a rather long wait. Thus, immunosuppressive therapy may be suggested in these cases.
    The Turkish journal of gastroenterology: the official journal of Turkish Society of Gastroenterology 10/2011; 22(5):494-9. DOI:10.4318/tjg.2011.0245 · 0.78 Impact Factor
  • S. Yapali · B. Bayrakci · F. Gunsar · G. Ersoz · Z. Karasu
    Journal of Hepatology 03/2011; 54. DOI:10.1016/S0168-8278(11)60401-7 · 11.34 Impact Factor
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    ABSTRACT: Matrix metalloproteinases (MMPs) are known to play an important role in cell migration during cancer invasion by degrading extracellular matrix proteins. This study aimed to determine the role of MMP-9 in hepatocellular carcinoma (HCC) carcinogenesis. Eighty-nine cases who underwent liver transplantation for HCC in cirrhotic liver were selected for this study. The tumor characteristics such as nodule number, maximal diameter, portal vein invasion, and the preoperative alpha-fetoprotein levels were reviewed. The intensity of immunostaining and the percentage of immunoreactive cells with MMP-9 were evaluated. All patients were evaluated for HCC recurrence and/or death, and cause of death was noted. There was a lower survival and more recurrence risk among participants with 4 or more nodules exceeding 3 cm in diameter, with poorly differentiated tumor, and with large-vessel involvement. Eleven patients developed recurrent HCC (12.4%). Twelve patients died as a result of HCC (13.5%). Among 89 HCCs, the incidences of a weak (+) and moderate (++) expression of MMP-9 in carcinoma cells were 30.3% (23/89) and 43.8% (39/89), respectively. Increased expression and intensity of MMP-9 were found to be inversely associated with poor tumor differentiation (P = 0.016, P = 0.009, respectively). A significant correlation between expression and intensity of MMP-9 and large vascular invasion (P = 0.01, and P = 0.03) was also observed. As far as prognosis is concerned, increased immunoreactivity and intensity of MMP-9 were found to exert an unfavorable impact on overall survival rates (P < 0.01, P = 0.01, respectively) and recurrences (P = 0.001, P = 0.02). Multivariate analyses revealed that MMP-9 staining percentage (P = 0.007) and portal vein invasion (P = 0.002) were independent predictors of survival, whereas the only independent predictor of recurrences was portal vein invasion (P = 0.007). In this study, our results indicate a positive association between MMP-9 expression and histopathologic parameters that indicate poor prognosis. We conclude that together, MMP-9 staining percentage and portal vein invasion in HCC may aid to predict poor outcome. Nevertheless MMP-9 staining percentage is expected to be a potential predictive marker on survival and needs to be studied more in detail.
    Liver Transplantation 05/2010; 16(5):621-30. DOI:10.1002/lt.22028 · 4.24 Impact Factor
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    ABSTRACT: Consuming wild mushrooms is an ordinary habit in late summer and autumn in our region. Every year, several cases of hepatic toxicity secondary to mushroom poisoning are observed because of poor identification of the mushrooms. Unfortunately some of them are fatal. Prometheus system is a newly developed extracorporeal liver support device for fractionated plasma separation and adsorption (FPSA) that enables removal of albumin-bound and water-soluble toxins. Therefore, it may be a promising treatment option for patients with liver failure due to mushroom poisoning. We studied 8 patients with mushroom poisoning. All patients underwent 1 to 4 consecutive FPSA (Prometheus)-system in addition to medical and supportive treatment such as fluid replacement, Penicillin G, N-acetylcysteine (NAC) and silymarin. A variety of clinical and biochemical parameters were assessed. We had improvement of the biochemical parameters after first treatment with FPSA-system. Seven of 8 patients survived and were discharged to resume an independent life. One patient who had grade III encephalopathy when admitted to hospital died. No major adverse events were observed during the application of this therapy modality. FPSA-system may be a safe and effective treatment option for patient with mushroom poisoning. Early hospitalization is essential in order to be successful. Controlled studies are needed to evaluate the efficacy of this new treatment choice on survival of patients with acute liver failure (ALF) due to mushroom poisoning.
    Hepato-gastroenterology 05/2010; 57(99-100):573-7. · 0.93 Impact Factor
  • N. G. Unal · F. Yilmaz · F. Gunsar · D. Nart · R. Vardar · Z. Karasu · G. Ersoz
    Journal of Hepatology 04/2010; 52. DOI:10.1016/S0168-8278(10)60344-3 · 11.34 Impact Factor
  • Journal of Hepatology 04/2010; 52. DOI:10.1016/S0168-8278(10)60739-8 · 11.34 Impact Factor
  • Journal of Hepatology 04/2010; 52. DOI:10.1016/S0168-8278(10)60184-5 · 11.34 Impact Factor
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    ABSTRACT: In patients with chronic hepatitis B (CHB) infection, precise definition of the hepatic fibrosis stage is the most important parameter to assess the risk of disease progression. Correlation between the prognosis of the CHB and the level of hepatitis-B virus DNA (HBV-DNA) is well considered in recent years. The aim of this study is to investigate the relationship between serum HBV-DNA level and histology of the liver. We also wanted to determine a threshold level of HBV-DNA for differentiation of low and high risk patients for progression. Two-hundred-fifty-nine patients with serum HBV-DNA level > 2000 copies/mL, determined by polymerase chain reaction (PCR), and biopsy proven naïve CHB infection were evaluated. Liver biopsies were evaluated histopathologically according to the Ishak scoring system. Laboratory values such as aspartate aminotransferase (AST), alanine aminotransferase ratio (ALT) were tested every 3 months and the highest value of each patient was evaluated. Mean age was 40 +/- 11 and 60% (155/259) of the patients were male. Mean laboratory values were as follows: AST: 52 +/- 46 U/L, ALT: 93 +/- 133 U/L, PLT: 224 +/- 60 1093)/l HBV DNA: 5.9 +/- 1.5 log copies/mL. In histological evaluation, mean inflammatory score was 4.34 +/- 2.72 and fibrosis score was 1.38 +/- 1.46. The fibrosis score was 0 or 1 in 63.3% (164/259) of the patients. The relationship between HBV-DNA level and histologic grade/stage was investigated and 15.000 copies/mL HBV DNA level was found as the threshold level to describe the activity of the disease. Fibrosis score was < 2 and/or grade < or = 5 in the patients who have HBV-DNA value below that level. In patients who have serum HBV-DNA level < or = 15000/copies/mL, histological activity was almost always low, and it seems that these patients do not need a liver biopsy regardless of hepatitis-B-e antigen (HBeAg) status.
    Hepato-gastroenterology 01/2010; 57(101):908-12. · 0.93 Impact Factor
  • Z Karasu · S Akay · F Yilmaz · U Akarca · G Ersoz · F Gunsar · M Kilic
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    ABSTRACT: Although end of treatment virological responses are similar in posttransplant patients with recurrent chronic hepatitis C virus infection and nontransplant patients, the sustained virological response rate is lower in the posttransplant setting. We investigated the efficacy of a longer duration (3 years) of therapy. Thirteen patients with biopsy-proven recurrent hepatitis C were included in the study. In the first year of therapy, all patients were treated with a standard regimen of interferon alpha 2b 3MU 3 times in a week plus ribavirin (800 to 1000 mg/d). After the availability of pegylated interferon, patients were converted to pegylated interferon (1.5 microg/kg body weight). Hepatitis C virus RNA was evaluated at months 3, 6, 9, 12, 24, 36, and 42. If hepatitis C virus RNA was negative at month 12, the patients continued treatment for 36 months. Hepatitis C virus RNA was negative in six patients at 12 months, including two who became hepatitis C virus RNA negative after 3 months; two, after 6 months; and two, after 12 months of therapy. Those six continued treatment completing 3 years of treatment with a sustained virological response. Four of those six patients with sustained virological response required colony-stimulating factors during treatment. Although the hepatitis C virus RNA status of patients at 12 weeks is a good marker to predict a sustained virological response in the nontransplant setting, it is not valid in posttransplant patients. A prolonged duration of therapy for patients who are viral responders at 12 months may prevent recurrence and increase the sustained virological response rate.
    Transplantation Proceedings 11/2009; 41(9):3806-9. DOI:10.1016/j.transproceed.2009.06.212 · 0.98 Impact Factor
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    ABSTRACT: To investigate the macrophage migration inhibitory factor (MIF) expression and -173 G/C polymorphism of the MIF gene in nonalcoholic fatty liver disease (NAFLD). Ninety-one patients with diagnosis of NAFLD and 104 healthy controls were included in the study. MIF -173 G/C polymorphism was detected using the PCR-restriction fragment length polymorphism based method. NAFLD was stratified as nonalcoholic steatohepatitis (NASH), probable NASH and steatosis, respectively in groups 1, 2 and 3, according to NAFLD Activity Score. MIF expression was detected by immunohistochemistry staining. Mean age of the patients was 50.1+/-9.6 years, and 54 of them were male. Serum alanine aminotransferase and aspartate aminotransferase were 50/83, 42/63 and 31/32, respectively in groups 1, 2 and 3, (P<0.05). Both the MIF expression of hepatocytes and mononuclear cells were more prominent in groups 1 and 2 than group 3. There was no correlation between MIF expression of hepatocytes and fibrosis stage. However, MIF expression of mononuclear cells significantly increased according to fibrosis stage (P<0.05, R : 0.2). There was no significant correlation between MIF genotype and MIF expression in the liver. MIF expression is significantly increased especially by mononuclear cells in liver tissue of patients with NASH secondary to inflammation. Thus, it should be considered as a consequence not a causal factor.
    European journal of gastroenterology & hepatology 10/2009; 22(2):192-8. DOI:10.1097/MEG.0b013e328331a596 · 2.25 Impact Factor
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    ABSTRACT: Non-alcoholic fatty liver disease (NAFLD) is common in obese and diabetics. Serine protease inhibitor Kazal-1 (SPINK-1) protein is highly expressed in the liver and adipose tissue of diabetic and obese suggesting its role in NAFLD. SPINK-1 also behaves as an acute phase reactant protein. Some genetic factors including the genetic variations in SPINK-1 protein have been linked to chronic pancreatitis and diabetes. We therefore hypothesized that SPINK-1 mutations might be a risk factor for the development of NAFLD. Liver biopsy proven fifty NAFLD cases (20 steatohepatitis, 30 diffuse fatty liver disease and 44 healthy controls were included to the study. Liver function tests were measured. Body mass index was calculated. Insulin resistance was determined by using a homeostasis model assessment (HOMA-IR). Ultrasound evaluation was performed for each subject. Common genetic mutations in the third exon of SPINK-1 gene were analyzed by direct sequencing method. We found two cases with a SNP at N34S location in NAFLD group (allele frequency %4). One subject with diffuse fatty liver disease and other with liver cirrhosis due to NAFLD had N34S mutation. No SNPs were detected in healthy controls. In conclusions, in limited number of patients SPINK-1 mutations were not considered as a risk factor alone for NAFLD development.
    Annals of hepatology: official journal of the Mexican Association of Hepatology 04/2009; 8(2):116-9. · 2.07 Impact Factor
  • N. Oruc · G. Ersoz · F. Yilmaz · F. Gunsar · Z. Karasu · O. Ozutemiz
    Journal of Hepatology 04/2009; 50. DOI:10.1016/S0168-8278(09)60164-1 · 11.34 Impact Factor
  • Journal of Hepatology 04/2009; 50. DOI:10.1016/S0168-8278(09)60999-5 · 11.34 Impact Factor

Publication Stats

833 Citations
568.47 Total Impact Points


  • 2000–2015
    • Ege University
      • Department of Gastroenterology
      Ismir, İzmir, Turkey
  • 2010
    • Qazvin University of Medical Sciences
      Kazvin, Qazvīn, Iran
  • 2008
    • University of Wisconsin–Madison
      Madison, Wisconsin, United States
  • 2004
    • Izmir University
      Ismir, İzmir, Turkey
  • 2003
    • Celal Bayar Üniversitesi
      Saruhan, Manisa, Turkey